To empty the tank...to let the boys go swimming... I’m talking about jacking your dick ladies and gentlemen. When a man gets backed up, he needs to filter, to get out with the old, and bring in the new. Without filtering you’d get prostate cancer.
by STEPMOMPINGASRRR December 18, 2018
underwear; briefs; panties

The Martha & The Muffins song off the _This Is The Ice Age_ album from the early 1980's entitled "Boy Without Filters" might have been the genesis of the term. Also one needs to include the image and function of cigarette filters and coffee filters.

What they're filtering is left up to the user: gas, sweaty ball odor, snatch stench, overpowering sexual passion, etc.
I gotta buy some new filters. The elastic's shot on this pair.
by Chris February 7, 2005
To pull down your pants and fart, removing the filtering provided by clothing.
Brandon walked up to Daniel and dropped a no filter at his desk.
by Adern May 25, 2008
The act of drinking an alcoholic beverage through a prostitute's used (and still warm) underwear.
Dan got extremely pissed and contracted oral herpes after filtering a pint of beer.
by Filter-Boys November 27, 2008
When something(person, situation, story) is essentially made to, or even edited to seem not as bad as it is. Extremely similar to being fake.
She was so filtered, she acted like it wasn't that big of a deal to see her ex when he still clearly wants to be with her and then lied about it.
by Hannigramn January 2, 2017
A woman that has been screwed so many times, that it wouldn't gain you any respect or self-dignity to have sexual intercourse with her. Hence the word "tap". She is liked tapped water.So in that case, she has been filtered.
"Dude! Don't do it with Ashley. She's been filtered!"
by SierraWithoutTheMist April 21, 2009